This theory was first put forward in 1997 by physicist Juan Maldacena. He said gravity arises from extremely thin vibrating strings. This "intricate world of strings", he said, exists in nine dimensions of space and another of time, and would be merely a hologram.

Maldacena said real life took place in a much "simpler, flatter cosmos where there is no gravity".

Scientists have previously compared this theory of the universe to a hologram on a credit card.

Kostas Skenderis, of the University of Southampton, explained this earlier this year: "The idea is similar to that of ordinary holograms where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card, but now it is the entire universe that is encoded in such a fashion."

Maldacena's idea excited scientists because it appeared to solve inconsistencies between quantum physics and Einstein's theory of gravity. It effectively provided physicists with a "duality" that meant they could move back and forth between the two ideas and solve problems.

Numerically confirmed

Now, new research carried out by Yoshifumi Hyakutake of Ibaraki University in Japan, suggests that Maldacena's theory could be true.

While not providing definitive proof, two papers have provided "compelling evidence" supporting the hologram theory.

In one, researchers looked at the internal energy of a black hole, the position of its event horizon (the boundary between it and the universe) and a number of other properties based on the string theory. They also took into account virtual particles that pop in and out of existence.

In the other paper, the team calculated the internal energy of lower-dimensional cosmos where there is no gravity.

After comparing the two findings from both papers, they found the calculations matched, suggesting the theory is correct.

Leonard Susskind, a theoretical physicist at Stanford University in California and one of the first theoreticians to explore the idea of holographic universes, said: "They have numerically confirmed, perhaps for the first time, something we were fairly sure had to be true, but was still a conjecture - namely that the thermodynamics of certain black holes can be reproduced from a lower-dimensional universe."

Maldacena noted that while neither model universes created by the Japanese researchers resembles the theory he put forward, he said the numerical proof showing two apparently separate worlds were identical provides hope that the gravitational properties of the universe can one day be explained.

"It seems to be a correct computation," he said. "The whole sequence of papers is very nice because it tests the dual [nature of the universes] in regimes where there are no analytic tests."